One question bothers me a long time and I am not sure if there is anyone that thinks about this before. Let's say you invested $10K in Bitcoin when the price was $20K, and some time later the price pumped to $40K, which means the initial capital is now worth $20K. For some reason, you need cash urgently so you decide to sell the Bitcoin you own for cash. You do it and now you have that $20K on hand.
In this process of trading, your profit is $10K for sure, regardless of whether the Bitcoin price will pump or dump. If you won't invest again, this beautiful success should be what you are proud of. However, 99% of us will choose to buy again and hope for the next success. However, now you buy at $40K and the price may drop to a new low below $20K later, and the profit you gained from last trading may be eaten up gradually by the market dump.
Connect the two dots(two extreme conditions) and draw a curve, high chances are that at last, your profits from all investments may not be that much, at least much less than what you expected when you first gained that $10K. Therefore, all the occasional profits between investments may become fixed or variable costs that these investment must pay.
Does this sound logical to you ? What do you think of all the interval losses from the investment gains ? Please let me know.
What you are describing is not investment cost but rather you flip-flopping between selling and buying at the wrong times, which eats away your profit in two ways:
the first way is that you obviously get scared of the dump and sell lower than you bought. Then the price rises and you buy again because you think it will continue going up, without you. Repeat process until you have no money.
The second way, which most people underestimate, is you grind away your money with trading fees. 0.1% and 0.1% and again and again until you have grinded away 10% from your repeated and unnecessary back and forth trading.
The only real investment costs should be the withdrawal fees and the one-time buying fee. Thats it. After that you hodl.
And if you are susceptible to panic-selling or panic-buying, then walk away from the computer and distract yourself with something else at least for a few years. Investing into Bitcoin takes discipline.